Sequential switch arrangements for operating electrically controlled locks

ABSTRACT

A sequential switch is composed of a plurality of ganged multicontact switch pairs connected in series, a current path being established to operate a lock when a switch of each pair is set to the correct contact. In a second embodiment, a variable digit sequential switch, the ganged pairs are connected so that a switch of an even number of pairs must be set to the correct contact to close the current path.

[ 1 June 5, 1973 United States Patent Lin 3,611,287 l0/l97l SEQUENTIAL SWITCH ARRANGEMENTS FOR OPERATING ELECTRICALLY CONTROLLED OTHER PUBLIC/TONS LOCKS Improved Electronic Locks Popular Electronics [76] Inventor: January 1968 page 73 Min-Shung Lin, 28- Park Road 3/F, Taipei, Taiwan Apr. 20, 1971 Primary Examiner-J. D. Miller Assistant Examiner-Harry E. Moose, Jr. Attorney-Michael S. Striker [22] Filed:

Appl. No.: 135,570

[57] ABSTRACT A sequential switch is composed of a plurality of ganged multi-contact switch pairs connected in series,

.E05b 49/00 .317/134, 135, l54;

[58] Field of 'fi' 70 277 278 a current path being established to operate a lock when a switch of each pair is set to the correct contact. In a second embodiment, a variable digit sequen- References Cited UNITED STATES PATENTS tial switch, the ganged pairs areconnected so that a switch of an even number of pairs must be set to the correct contact to close the current path.

3,450,953 6/1969 Gardner............ ...................317/134 3,309,542 3/1967 Elliot............................. ..317/154 X 9 Claims, 13 Drawing Figures PATENIELJ'JN suns I 3,737,733

sum 1 [1f 5 karma-1 ATTORNEY PATENTED 51973 -SHEEI 2 BF 5.

FIG. 5.

v FIG. 8

INVENTOR M 'Smma I. II) 1,

FIG. 7

ATTORNEY PATENTELJUH 51973 Sum 3 [IF 5 INVENTOR Ina-n00: ow (a 1 0 ATTORNEY PATENTEDJUH' 5191a SHEET 5 BF 5 I INVENTOR I'm-sauna 014/ ATTORNEY SEQUENTIAL SWITCH ARRANGEMENTS FOR OPERATING ELECTRICALLY CONTROLLED LOCKS BACKGROUND OF THE INVENTION The invention relates to electrically operated locks for safes and vaults.

The prior art contains a number of sequential locks that are operated without a key. These known sequential locks, however, because they are purely mechanical in operation, can be opened by a clever burglar.

SUMMARY OF THE INVENTION An object of the invention is a sequential switch lock that can be opened only by knowing its code.

Another object of the invention is a variable digit sequential switch that has a very large number of possible codes for a relatively small number of ganged switch pairs.

The invention consists essentially of at least one pair of multicontact switch means, each switch means having a set of contacts, conductor means connecting a selected contact of one switch means to a selected contact of the other switch means of said pair; movable means comprised by each said switch means forcontacting each contact of said set to make an electrical connection between said movable means and each contact, and a circuit including lock operating means, said circuit being electrically connected to said movable means, whereby when said movable means of both said switch means are in electrical contact with the respective selected contacts said circuit is closed.

The novel features which are considered as characteristic for the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with .additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a schematic plan view of a switch suitable for use with the invention;

FIG. 2 is a schematic plan view of two interconnected switches;

FIG. 3 schematically shows a sequential switch of the invention;

FIGS. 4 and 5 are diagrams of circuits, using a sequential switch of the invention, for operating the lock of a safe;

FIG. 6 is a wiring diagram of a circuit suitable for a house or hotel room;

FIG. 7 is a wiring diagram of a vehicle ignition lock arrangement;

FIG. 8 is a detail of the mechanical construction of the embodiment shown in FIG. 7;

FIG. 9 is a wiring diagram of a variable digit sequential switch of the invention;

FIGS. 10 and ll are isometric views of a safe incorporating a variable digit sequential switch;

FIG. 12 is a detail of the mechanical construction of the lock of the safe; and I FIG. 13 is a diagram of a circuit suitable for the safe shown in FIGS. 10 and 11.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The switch, or dial, of a sequential switch is composed of an even number of contacts. The number of switches in the embodiment of FIG. 2 can be even or odd. The structure of a dial is shown schematically in FIGS. 1 and 2.

A switch is made of electrically insulating material divided into a stator and a rotor, as shown in FlG. I, wherein A denotes the second member or stator and B the first member or rotor. The inner face of the stator ring has embedded therein 10 metal contacts d, numbered from 0 to 9. A wiper c is shown on rotor B. When the rotor turns about the central axis, wiper c contacts successive ones of the contacts 0!. A wire a is connected to the wiper 0. FIG. 1 shows a respective wire 1 to 1 connected to the corresponding contact 0 to 9.

Two switches connected together so that a contact wire of one is connected to a corresponding contact on the other dial are called ganged switches, or dials. The term ganged as herein used does not mean that the rotors of two or more switches are mechanically coupled together. A current path is formed only when both rotors of two ganged switches are rotated to the same corresponding contact d: in other words, when the rotor of one switch is rotated to contact 3 and the rotor of the other switch is also rotated to the contact 3. FIG. 2 shows a pair of ganged switches, having wiper wires a and b. The two switches of the pair will be electrically connected together when both wipers contact the respective contacts 5 of their stators, in the particular example shown.

FIG. 3 schematically shows a sequential switch composed of four pairs of ganged dials, X and Y X and Y X and Y X and Y Only when X-,=Y X =Y,, X =Y and X =Y simultaneously is there a current path from a to b. This means, for example, that contact 1 of X is connected to contact 1 of Y contact 5 of X is connected to contact 5 of Y contact 3 of X is connected to contact 3 of Y and and contact 7 of X is connected to contact 7 of Y Only one corresponding contact d of a pair of ganged switches is connected together. Therefore, each switch of a ganged pair must be set to the right number. Any inequality caused when two switches of a ganged pair are not set to the same correct number will result in an open circuit between a and b. If the switches Y Y Y and Y., are mounted inside a safe with the switches X X X and X accessible from the outside, and the latter rotated until the four equalities are satisfied in order that a and b are connected together, then the safe can be opened. This will be explained in detail. The connection between each ganged pair is made to the users liking, and the sequential switch can be extended to include more than four ganged pairs.

This switch can be utilized to control an electromagnet, which in turn controls the movement of a lock for the safe.

The sequential switch of the invention virtually ensures that the safe cannot be opened by someone not privy to the correct setting of each ganged pair.

For convenience, point a will be considered the input of the sequential switch, and point b the output.

FIG. 4 shows a simple circuit to operate an electromagnet L,, which latter controls the lock of a safe. The

box 10 denotes a sequential switch of the kind described in connection with FIGS; 1, 2 and 3. The power supply can be either a.c. or d.c., the supply being hidden inside the safe. K, is a pushbutton switch. When a and b are connected together by the appropriate turning of the deals, L, will be energized as soon as K, is pushed. Once L, is energized, 12, which is a switch controlled by L,, will be closed. L, will retain its attractive force even after switch K, is released, because 12 and K are closed. To lock the safe one need only to open K and to turn the dials randomly.

The embodiment shown in FIG. is similar to the embodiment shown in FIG. 4, but with an added alarm. Parts having the same function as in the previous form of the invention are denoted by the same reference numerals. The alarm operates on 3 volts d.c., 13 being one coil of this alarm, and 14 being the other, wound in the opposite direction relative to 13. If a and b are connected together, pressing K, will magnetize L,, exciting 13 and 14. The lock then opens, but the bell 17 will not ring because 13 and 14 are wound in opposite directions. If K, is pressed with a and b open, only 13 is energized. The alarm will sound. A thief must succeed on the first try or else the alarm will give warning. Resistors l5 and 16 are inserted to drop the voltage to 3 volts for 13 and 14. T, and T are rectifiers. Their purpose is as follows. When 13 rings the alarm, the fluctuating current in 13 will induce a back EMF across the terminals of 14. T, and T, block this voltage from reaching L, so that the safe cannot be opened accidentally. More complex circuits can be designed. The one shown here is only offered as an example of an application of the sequential switch. 7

The embodiment shown in FIG. 6 shows the sequential switch of the invention as applied to a private house or a hotel room to prevent the entry of a burglar. Fundamentally, it operates in the same way as the embodiment of FIG. 5. In addition to the components of the circuit shown in FIG. 5, the embodiment of FIG. 6has a triple-pole push-button indoor switch 24, an indoor locking switch 23, an outdoor locking switch 22, and a switch 18. The sequential switch is denoted by the box 10. When the owner wants to go out he presses 24, and

. coils L,, 13, and 14 are excited simultaneously. The

lock, which is operated by L,, is opened, and the alarm 17 is not actuated. 12 and 18 are closed by the magnetization of L,. Hence, if 24 is released, current will continue to flow through L,. The reason that a triple-pole switch is used for 24 is that the instant that 19, 20 and 21 are connected, current will pass through 14. Switch 12 does not'close until L, is energized by the closing of 19, 20 and 21.

Unless current flows through L,, 13, and 14 at the,

same time, the alarm 17 will sound. This is avoided by connecting 19, 20 and 21 simultaneously. The owner can lock indoors by pressing 23 and lock outdoors by pressing 22.

The switch 18 is also useful in that when the owner enters, he can turn the dials of at random so that a steady current is maintained in L, through switch 12 and switch 18, the latter shunting the sequential switch 10, the dials of which are randomly turned.

The embodiment shown in FIGS. 7 and 8 illustrates a circuit to control the closing of the ignition circuit of a motor vehicle, such as a taxi.

L, is used to attract the plunger which is fabricated as the lock inside the hood of the vehicles. Thieves are unable to open the hood and connect the circuit leading to the spark plugs directly. When L, attracts the plunger, the hood is unlocked.

The sequential switch 10 is installed in a box 28 next to the steering wheel and near to the dashboard of the automobile. Switches 27 and 28 are placed in the box. The lock on the box is controlled by electromagnet 29. When 29 is energized, the box is unlocked. 1

With reference to FIG. 8, an electrically insulated cylinder 31 is drilled with a rectangular key hole 34. A protruding metal block 32 is shown on the cylinder. A spring is hidden inside 32 so that it is urged in the direc* tion of arrow E. The driver, after entering the vehicle, moves the dials on the sequential switch 10 to establish an electrical path between points a and b. Then he closes switch 27 and proceeds in the manner as will be explained. Once the vehicle is started, the driver again moves the dials of 10 to open the path between a and b.

An iron bar 33 is under the control of electromagnet 30, and is attracted in the direction of arrow B when 30 is excited. Turning cylinder 31 in the direction of the arrow D will cause the metal block 32 to contact a metal contact (not shown) and an electric path is formed.

, After a and b are connected and 27 closed, the circuit of the automobile is connected by the procedure just described. As soon as the circuit is made, the dials are turned so that the electromagnet 30 is deenergized. The bar 33 returns to its original position. The circuit is open if the cylinder 31 is rotated in a direction opposite to that of arrow D. The metal block 32 will be disconnected from the aforesaid metal contact and the ignition is opened. Even though the bar 33 is returned to its original position, the block 32 can still compress in the E direction.

L, and 29 control 26 and 25, respectively. When L, and 29 are energized, 26 and 25 are closed. They operate similarly to switch 18 in the embodiment'shown in FIG. 6.

There will now be described the operation and construction of the variable-digit sequential switch.

With reference to FIG. 9, B,, B B are ganged switches, or dials. A,, A A,, are electromagnets composed of two windings with the same turns wound in opposite direction. Electromagnet A, governs the movement of d, only, which latter is a thin metal spring, whereas A, governs d, and (1,, A,, governs d, and 11,, and so forth. The position of the spring d, is controlled by electromagnet A,.

For the sake of convenience, the points P and Q will be considered respectively the input" and the output of the variable digit sequential switch.

When A, is energized, contact is made between d, and c,. When A, is not energized, d, is connected wit by.

When A, (where i 2 to 9) is energized, contact is made between d, and 0,, and between d, and c,'. When A, is not energized, d, contacts b,, and d, contacts b,'.

Switches 0,, 11,, a, are assembled on a common shaft, so that when a,, a, are closed, a, is open. These three switches constitute a selector called D,.

a and a are assembled on selector D Unless D, is turned, switch a,,, remains closed and switch a,,, remains open. If selector D,., is turned, then a,,, is opened and a is, closed. I

Similar reasoning applies to 11,, a}, a,, and a, (where i= 2 through 9). Unless selector D, (where i= 2, 9) is turned, a,', afi, a, remain closed and a, is open.

When D, is turned sufficiently, the above switch connections are reversed.

Once we choose an even number of selectors from all D,s (where i now l, l) and turn them, what will happen? The following illustration provides the answer.

If D,, D D and D,,, are moved from their neutral position and X,, X X and X are set equal to Y,, Y Y and Y,,,, a conductive path is established between P and Q, as will be explained, step by step.

Having turned D,, D D and D,,, from their netrual position, a,, a}, a af, a a c a a,,, are opened, but a,, 0, a a,,, are closed.

Since D D D D,,, D-,, D remain unchanged in their position, a a a a a a a a a a 0 a a a a a a and a remain closed, while a (1, a a a and a remain open.

Therefore, the following switches are closed: a,, a 2 2 s 3 3 "4 s, 5 s 6 6 s, 1111, 1 7 8 s 9 s and 10 The following switches are open: a,, a}, a a a 4 a 1 4 1 4 4 I s s 7 s 8 s 7 s and m It is assumed in FIG. 9 that current flows from negative to positive. As soon as the switch K is closed, current flows from K to P, through L to r,, and to the positive pole of the power supply 11. No current flows through L,, since a, is open. Therefore, electromagnet A is energized. Spring d,, attracted by A,, contacts c,, so that no current flows through b,; therefore, no current flows through L and L of A a, is open and a, is closed. Part of the current flows through L,, while the other part flows through the path 0, to d, to a,, and through ganged dials B to b Neither L or L, of A is energized, so 11 and d, will not be attracted by A and d contacts b and d contacts b Current reaching b flows along the path a to b, to a, to b.,. Current also flows along the path b, to B to a, to b,,, since a, is open and a, is closed. Consequently, no current flows through the coils of A A and A,,. d, remains in contactwith b d, with b,,, d, with b,, and d, with b,.

Since A, is unenergized, current reaching a, follows two paths: a first path consisting of b, to L to a to r,,,; and a. second path consisting of b, to L, to r,,. Both of these paths end at the positive pole of the supply 11.

Current in both L and L produces cancelling fields, making A, passive and leaving d incontact with b,,, and

' d, in contact with b,,'.

There is also another path from the connection b,, in addition to the two just described. This other path is b, to a, to b,. At this point the path .has-two branches, a first consisting of path L to a, to r to supply 11; and a second, consisting of L to r to supply 11. Current in both L, and L, render A, passive, so that d, and b, are connected and d, and b, are connected.

Current at b flows to a, to b, from where it separates into two branches, a first branch consisting of L, to a, tor to source 11, and a second branch consisting of L, to r,, to 11. As a consequence of current flowing through bothwindings, d, remains in contact with b, and d-, remains in contact with b-,.

Current passing through b, will also follow a second path: b, to a, to b, to L, to r 'to 11. A, is energized, and d, and d, are respectively disconnected from b and b, and connected to c and c Since d is disconnected from b A, is unenergized, and 11,, remains in contact with b, and d, in contact with At connection b the current takes two paths, a first consisting of b to c, to a, and through B to 0,, and a second consisting of b to b, to a, and through 8,, to (1, d, is connected with c and a is open.

Since a is open, A, is not energized, and 11,, remains in contact with b, and d,, in contact with b,,'.

Current passing through the ganged pair B returns to the supply 11 through 0 and the load L. Thus, there is formed a closed path.

A closed path between P and Q is made if any evennumber of selectors are turned. What is illustrated above is only an example. Usually the power supply will be d.c. The polarity of the battery can be reversed. An a.c. source can be used if there are taken into consideration the frequency of the ac. source, the attraction of A,, A A and the restoring force of d,, d d d d, which are governed by A,, A A

The resistors r, (i l, 2, 18) are used because the voltage rating of the coils is small. The series connection of these resistors shares a portion of the voltage. If the coils of A, are properly designed, r, can be discarded.

When mounting this variable-digit sequential switch in a safe with the X dials (contained within the broken line box in FIG. 9) it is not necessary to use all of the dials. As shown in the above example, if X ,=Y X.,=Y X =Y and X,,,=Y,,,, then a closed path is made. Any even number of selectors D, and of the corresponding ganged dials B, is suitable.

The total possible combinations of this arrangement are C X 10 C, X 10 C," X 10 C X 10 C X 10" 14 billion. The variable digit sequential switch of the invention is suitable for all safes and vaults in which valuables are kept.

For example, if we let X,=Y,=3, X.,=Y.,=l X ,,=7, and X,,,=Y, =0, the code is 3170. D,, D.,, D, and D, are turned from their normal position beforehand. The X,, X X and X,,, dials are set to their correct positions. K is then closed, and the lock is opened. Only the X dials, the switch K, and the power supply plug and socket are exposed. Everything else is inside the safe or vault.

With reference to FIGS. 10 and 11, there is shown the way in which the variable digit sequential switch of the invention is built into a large safe 35 having a central partition 53. The safe could also be a vault. The safe has two doors 36 and 37 with respective handles 38 and 39. The reference numerals 40, 41, and 42 respectively denote the master opening switch, the switch for opening door 36, and the switch for opening door 37, as will be made clear in connection with FIG. 13. Ten exposed dials 43, five in each door, are rotatably mounted in the boxes 44 and 45 secured to the inside of the safe doors. The rotatable vertical shafts 46 of these dials are drivingly connected to corresponding dials completely hidden from view in the boxes 47 and 48, also secured to the inside of the respective doors 36 and 37. These latter, hidden, dials correspond to the dials X,, FIG. 9. The 10 dials 49 (only four are shown), projecting from the boxes 50, correspond to the dials Y in FIG. 9 and are exposed when the safe is open to permit the code to be changed at will, since only those Y dials are correctly set that correspond to the code chosen. In the X shown within the broken-line box in example previously given, the Y dials 1, 4, 8, and are respectively set to the numbers 3, l, 7, and 0, but the remaining Y dials are not correctly set.

The two metal boxes 51, which are spot welded, or otherwise fixed, to the doors'36 and '37, each house the lock mechanism for the respective door, and the electromagnet for operating the lock.

The nine electromagnets A A of FIG. 9 are held underneath the safe floor 52.

The selectors D to D previously described in connection with FIG. 9, are mounted at the base of the safe, and are exposed when the safe is open. Only those selectors are turned beforehand that correspond to the ganged dial pairs of the code.

The selectors D are always mounted inside of the safe, whereas either the dials X or the dials Y (but not both!) can be the dials that are operated from outside of the safe by turning the exposed dials 43.

Each lock mechanism, one of which is shown in FIG. 12, operates respective vertical door locking rods 54 and 55, and a horizontal locking rod 56. The respective door handle 38 or 39 can turn a cam 57 clockwise, to lock, and counterclockwise, to open, the door. Assuming that the safe is to be locked up, the cam 57 is turned clockwise, in the direction of the arrow, pushing the vertical rods 54 and 55 respectively up and down, as shown by the arrows, and the horizontal rod 56 to the left. The springs 58 urge these rods against the lobes of the cam 57.

The cam incorporates a pole 60 that accepts a spring biased bolt 59 that is normally urged to enter the hole 60. This bolt is controlled by a respective one of the electromagnets 61 or 62, shown in FIG. 13. When the hole 60 is aligned with the withdrawn bolt 59, the controlling electromagnet 61 or 62 is turned off, causing the spring biased bolt 59 to shoot into the hole 60, thereby locking the door handle. The locking bar 54, 55, 56 have previously been moved to their locking positions by the rotation of the cam 57.

FIG. 13 shows a circuit, broadly similar to those shown in FIGS. 5 and 6, suitable for the safe just described. The variable digit sequential switch, shown in FIG. 9, is denoted by 63. The points P, Q, and m are the same as the similarly referenced points in FIG. 9.

Those components having the same function as in the circuits of FIGS. 5 and 6 are denoted by the reference numerals of these latter Figures.

The safe door mounted switches 40, 41, and 42 are bridged by respective switches 65, 66, and 67, which arerespectively controlled by the electromagnets 64, 61, and 62 and closed when the latter are energized. A switch 68, operated to close by the electromagnet 64 when the latter is energized, shunts the variable digit sequential switch 63.

A push button switch 69 is provided for locking the safe. The circuit also comprises an alarm 17 and the two diodes T and T The electromagnets 61 and 62, as previously explained, operate the bolt 59 of a respective door 36 or 37. Each electromagnet 61 and 62 is advantageously held in the box 51 of a respective door. If only door 36 is to be opened, first switch 40 and then switch 41 are pressed. If only door 37 is to be opened, first switch 40 and then switch 42 are pressed.

It will be understood that each of the elements described above, or two or more together, may also find a useful application in other types of circuits and constructions differing from the types described above.

While the invention has been illustrated and described as embodied in sequential switch arrangements for operating electrically controlled locks, it-is not intended to be limited to the details shown, since various modifications and structural changes may be made without departing in any way from the spirit of the present invention.

Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can by applying current knowledge readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention and, therefore, such adaptations should and are intended to be comprehended within the meaning and range of equivalence of the following claims.

What is claimed as new and desired to be protected by Letters Patent is set forth in the appended claims:

1. Switch arrangement for use in electrical combination locks, comprising in combination a pair of multiposition switches settable independently of each other, each including a first member having a first electrical contact thereon, and a second member having a plurality of second electrical contacts thereon, one of said members of each switch being movable relative to the other of said members of the same switch in a sense effecting electrical connection between said first contact and any of said second contacts; connecting means for electrically connecting at least a predetermined one of said second contacts of one of said switches to a predetermined one of said second contacts of the other of said switches, whereby a current path between said first contacts is formed only when said first contacts are electrically connected with said predetermined ones of said second contacts; electrical lock-operating means connected in circuit with said first contacts, and includ ing electromagnet means, first normally open switch means connected in series with said electromagnet means and with said first contacts, second normally closed switch means connected in series with said electromagnet means and said first contacts, and normally open third switch means shunted across said first switch means and closed by said electromagnet means when the latter is energized; alarm means for generating an alarm signal upon closing of said first switch means when said first contacts are not electrically connected with said predetermined ones of said second contacts and including first and second coils wound in opposing senses and circuit means conntecting said coils with said switches and with said lock-operating means for effecting energization of both of said coils when said first switch means is closed and said first contacts are connected with said predetermined contacts, and for effecting energization of only one of said coils when said first switch means is closed and said first contacts are not connected with said predetermined contacts.

2. An arrangement as defined in claim 1, including diode means connected to prevent a voltage induced in the other of said first and second coils from reaching said electromagnet means when only said one coil is energized.

3. An arrangement as defined in claim 21, one of said fourth switch means being connected between one side of said current source and said output; normally open fifth switch means connected between said input and said output and operated by said electromagnet means to close when the latter is energized; normally open triple-pole switch means having two poles respectively connected to said input and output and a remaining pole connected to one side of said current source means.

4. Switch arrangement for use in electrical combination locks, comprising in combination at least three pairs of multi-position switches, the switches of each pair being settable independently of each other, and each switch including a first member having a first electrical contact thereon and a second member having a plurality of second electrical contacts thereon, one of said members of each switch being movable relative to the other of said members of the same switch in a sense effecting'electrical connection between said first contact and any of said second contacts; connecting means for electrically connecting at least a predetermined one of said second contacts of one of the switches of each pair to a predetermined one of said second contacts of the other of the switches of the same pair, whereby a current path between said first contacts is formed only when said first contacts are electrically connected with the respective ones of said predetermined second contacts, and including additional connecting means for connecting said first contacts in series; electrical lockoperating means connected in circuit withthe series connection of said first contacts, with the first contact of one of said switches constituting an input and the first contact of an other of said switches constituting an output; and further including a discrete first electromagnet associated with each of said pairs except that pair at said output, each said first electromagnet having a passive and an active state; a discrete first switch means operated by each said first electromagnet to move from a first to a second position when said first electromagnet is active; and'a discrete second switch means connected to each of said pairs and having first and second positions, whereby in said second position second switch means cooperating so that when saidsecond switch means is in said second position the associated pair is connected in said circuit provided that the movable means of said pair is in contact with the respective selected contacts.

5. An arrangement as defined in claim 4, as used to operate the lock of a safe or vault, wherein said lock operating means is a second electromagnet, and further including current source means; normally open third switch means connected in series with said second electromagnet, said second electromagnet and third switch means being connected between one side of said cur rent source means and said output, the other side of said current source means being connected to said input.

6. An arrangement as defined in claim 5, further including normally open fourth switch means connected across said third switch means and operated by said second electromagnet to close when the latter is energized.

7. An arrangement as defined in claim 6, further including normally open fifth switch means connected between said input and said other side of said current source means.

8. An arrangement as defined in claim 7, further including normally open sixth switch means connected across said fifth switch means; and a third electromagnet connected in parallel with said series connected second electromagnet and third switch means for operating said sixth switch means to close the latter when said third electromagnet is energized.

9. An arrangement as defined in claim 8, further including normallyopen seventh switch means connected between said input and output and operated by said third electromagnet to close when the latter is energized. 

1. Switch arrangement for use in electrical combination locks, comprising in combination a pair of multi-position switches settable independently of each other, each including a first member having a first electrical contact thereon, and a second member having a plurality of second electrical contacts thereon, one of said members of each switch being movable relative to the other of said members of the same switch in a sense effecting electrical connection between said first contact and any of said second contacts; connecting means for electrically connecting at least a predetermined one of said second contacts of one of said switches to a predetermined one of said second contacts of the other of said switches, whereby a current path between said first contacts is formed only when said first contacts are electrically connected with said predetermined ones of said second contacts; electrical lock-operating means connected in circuit with said first contacts, and including electromagnet means, first normally open switch means connected in series with said electromagnet means and with said first contacts, second normally closed switch means connected in series with said electromagnet means and said first contacts, and normally open third switch means shunted across said first switch means and closed by said electromagnet means when the latter is energized; alarm means for generating an alarm signal upon closing of said first switch means when said first contacts are not electrically connected with said predetermined ones of said second contacts and including first and second coils wound in opposing senses and circuit means conntecting said coils with said switches and with said lockoperating means for effecting energization of both of said coils when said first switch means is closed and said first contacts are conneCted with said predetermined contacts, and for effecting energization of only one of said coils when said first switch means is closed and said first contacts are not connected with said predetermined contacts.
 2. An arrangement as defined in claim 1, including diode means connected to prevent a voltage induced in the other of said first and second coils from reaching said electromagnet means when only said one coil is energized.
 3. An arrangement as defined in claim 21, one of said first contacts constituting an input and an other of said first contacts defining an output, and wherein said circuit means includes current source means; normally open fourth switch means connected in series with said first and second switch means, said first, second and fourth switch means being connected between one side of said current source and said output; normally open fifth switch means connected between said input and said output and operated by said electromagnet means to close when the latter is energized; normally open triple-pole switch means having two poles respectively connected to said input and output and a remaining pole connected to one side of said current source means.
 4. Switch arrangement for use in electrical combination locks, comprising in combination at least three pairs of multi-position switches, the switches of each pair being settable independently of each other, and each switch including a first member having a first electrical contact thereon and a second member having a plurality of second electrical contacts thereon, one of said members of each switch being movable relative to the other of said members of the same switch in a sense effecting electrical connection between said first contact and any of said second contacts; connecting means for electrically connecting at least a predetermined one of said second contacts of one of the switches of each pair to a predetermined one of said second contacts of the other of the switches of the same pair, whereby a current path between said first contacts is formed only when said first contacts are electrically connected with the respective ones of said predetermined second contacts, and including additional connecting means for connecting said first contacts in series; electrical lock-operating means connected in circuit with the series connection of said first contacts, with the first contact of one of said switches constituting an input and the first contact of an other of said switches constituting an output; and further including a discrete first electromagnet associated with each of said pairs except that pair at said output, each said first electromagnet having a passive and an active state; a discrete first switch means operated by each said first electromagnet to move from a first to a second position when said first electromagnet is active; and a discrete second switch means connected to each of said pairs and having first and second positions, whereby in said second position said first electromagnet associated with the pair to which said second switch means is connected is active provided that said movable means of the immediately preceding pair in the direction of said input is in contact with the respective selected contacts, said first and second switch means cooperating so that when said second switch means is in said second position the associated pair is connected in said circuit provided that the movable means of said pair is in contact with the respective selected contacts.
 5. An arrangement as defined in claim 4, as used to operate the lock of a safe or vault, wherein said lock operating means is a second electromagnet, and further including current source means; normally open third switch means connected in series with said second electromagnet, said second electromagnet and third switch means being connected between one side of said current source means and said output, the other side of said current source means being connected to said input.
 6. An arrangement as defined in claim 5, further including normally open fourth switch means connected across said third switch means and operated by said second electromagnet to close when the latter is energized.
 7. An arrangement as defined in claim 6, further including normally open fifth switch means connected between said input and said other side of said current source means.
 8. An arrangement as defined in claim 7, further including normally open sixth switch means connected across said fifth switch means; and a third electromagnet connected in parallel with said series connected second electromagnet and third switch means for operating said sixth switch means to close the latter when said third electromagnet is energized.
 9. An arrangement as defined in claim 8, further including normally open seventh switch means connected between said input and output and operated by said third electromagnet to close when the latter is energized. 